The World Health Organisation (WHO) and the United Nations Children’s Fund (UNICEF) recommend zinc supplementation for children with diarrhea.

However, low- and middle-income countries (LMICs) conducted the majority of the studies supporting this recommendation. Although the mortality rate of acute diarrhoea in developed countries is low, diarrhoea leads to a high number of clinical care and hospital admissions, which represents a significant economic burden. This systematic review assessed the therapeutic benefits of zinc supplementation in the treatment of acute diarrhoea in children living in high-income countries. We conducted a literature search on the Medline, Embase, Cochrane, and Scielo databases to find published randomised controlled trials on zinc supplementation and acute diarrhoea in children residing in developed countries. We conducted a systematic literature search of the databases, uncovered 609 titles, and included 3 trials, totaling 620 treated children with acute diarrhoea, after reviewing abstracts and full manuscripts for inclusion and exclusion criteria. Two studies showed that zinc did not interfere with the duration of diarrhea. According to the Cochrane Risk of Bias RoB2, risk was considered low in two studies and some concerns in another. There was no statistically significant reduction in the mean RR for the occurrence of diarrheal episodes after 7 days of zinc supplement administration (0.4% vs. 0.6%; RR 0.73; 95% CI 0.28-1.92; p = 0.53; I2 = 16%). Zinc supplementation did not reduce the duration of acute diarrhoea among children living in developed countries.

Whats is New

-Zinc supplementation did not reduce the duration of acute diarrhea among children living in developed countries.

-The anti-diarrheal effect of zinc is dependent on zinc deficiency.

-The WHO and UNICEF recommended regimen of therapeutic zinc should not include high-income countries.

Whats is Known

-Zinc supplementation may reduce the duration and severity of diarrhea in poor countries

-The World Health Organization (WHO) and the United Nations International Children’s Emergency Fund (UNICEF) recommend zinc supplementation for children with acute diarrhea

The authors have declared no competing interest.

This study did not receive any funding

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